Extending the ListViewItem

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace ListViewExtendedItem
{
    public partial class mainForm : Form
    {
        public mainForm()
        {
            InitializeComponent();
            colID.Name = "colID";
            colName.Name = "colName";
            colDate.Name = "colDate";
        }

        private void btnNew_Click(object sender, EventArgs e)
        {
            TestClass testObject = new TestClass(1, "Some name", DateTime.Now);
            objectPropGrid.SelectedObject = testObject;
            btnAdd.Enabled = true;
        }

        private void objectList_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (objectList.SelectedItems.Count == 1)
            {
                btnUpdate.Enabled = true;
                ListViewExtendedItem item = (ListViewExtendedItem)objectList.SelectedItems[0];
                objectPropGrid.SelectedObject = item.Data;
            }
        }

        private void btnAdd_Click(object sender, EventArgs e)
        {
            btnAdd.Enabled = false;
            ListViewExtendedItem item = new ListViewExtendedItem(objectList, objectPropGrid.SelectedObject);
            objectList.Items.Add(item);
            objectPropGrid.SelectedObject = null;
        }

        private void btnUpdate_Click(object sender, EventArgs e)
        {
            btnUpdate.Enabled = false;
            ((ListViewExtendedItem)objectList.SelectedItems[0]).Update(objectPropGrid.SelectedObject);
            objectPropGrid.SelectedObject = null;
            objectList.SelectedItems.Clear();
        }
    }
}